Table 3 Image quality NEMA results for the 4:1 contrast ratio (3D OP-OSEM+PSF + TOF, 4 iterations, 5 subsets, no post-filtering)

Sphere diameter (mm)

 10

75.4

83.3 (94.4)

5.3

6.3 (9.5)

 13

78.4

82.4 (88.0)

4.4

5.0 (7.3)

 17

91.0

93.2 (96.5)

3.4

3.7 (5.2)

 22

96.3

98.7 (101.8)

2.7

2.7 (3.8)

 28

76.7

77.6 (84.6)

2.3

2.3 (3.1)

 37

83.2

84.1 (89.9)

1.9

1.9 (2.5)

Average lung residual (%)

5.5

5.5 (3.2)